| 摘要 |
<p>PURPOSE:To lower a transmission speed without deteriorating the transmission quality of a moving picture by accumulating absolute values of the difference between the frames of the orthogonal transformation signal of a picture signal for every area obtained by dividing a block into the plural areas and encoding only the orthogonal transformation signal or the difference between the frames in the area having a larger accumulated value. CONSTITUTION:A decision circuit 12 compares the accumulated value for every area of the absolute value of the difference between the frames from an accumulation circuit 11 with a prescribed threshold and controls a switch circuit 5 so as to be closed only during a period when the accumulated value of the absolute value of the inputted difference between the frames exceeds the threshold. Therefore, from the switch circuit 5, only a signal in the area in which the accumulated value of the absolute value of the difference between the frames to the orthogonal transformation of a preceding frame outputted from a frame memory 8 on the orthogonal transformation signals of the respective blocks from an orthogonal transformation circuit 4 exceeds the threshold value is outputted. Thus, the orthogonal transformation signal selected in the switch circuit 5 is transmitted to a transmission path 7 through a buffer memory 6 in a constant bit rate, inputted to the frame memory 8 and the contents of the frame memory 8 are rewritten.</p> |
